Rhamnaceae
Deciduous or evergreen, often thorny trees, shrubs, woody climbers or lianes, rarely herbs. Leaves simple, petiolate, alternate or opposite, with 1 main vein or 3–5 veins, entire to serrate, sometimes much reduced; stipules small, caducous or persistent,
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D. Medan and C. Schirarend
Rhamnaceae D. MEDAN and C. SCHIRAREND
Rhamnaceae Juss., Gen. Pl.: 376 (1789) ('Rhamni'), nom. cons.
Deciduous or evergreen, often thorny trees, shrubs, woody climbers or lianes, rarely herbs. Leaves simple, petiolate, alternate or opposite, with 1 main vein or 3-5 veins, entire to serrate, sometimes much reduced; stipules small, caducous or persistent, sometimes fused intrapetiolarly or interpetiolarly, or transformed into spines, absent in most Phylica. Inflorescence basically cymose, cymes mostly axillary, sessile or pedunculate, or reduced to many-few-flowered fascicles. Flowers small, 3-6mm in diameter, regular, (3)4-5(6)merous, bisexual or unisexual, plants sometimes dioecious, haplostemonous, hypogynous to epigynous, yellowish to greenish, rarely brightly coloured; hypanthium patelliform or hemispherical to tubular, sometimes absent, at the rim bearing calyx, corolla and stamens; sepals 4 or 5, valvate in bud, triangular, erect to more or less recurved during anthesis, often keeled adaxially; petals 4 or 5, rarely 0, usually smaller than sepals, concave or hooded, rarely almost flat, often shortly clawed, often enfolding the stamens; stamens 4 or 5, antepetalous, filaments thin, adnate to the base of the petals, anthers minute, versatile or not, 2( 4)locular, dehiscing by longitudinal slits, usually introrse; disc intrastaminal, nectariferous, thin to more or less fleshy, entire or lobed, glabrous, rarely pubescent, free from ovary or tightly surrounding it, or adnate to the hypanthium; combined pubescence of hypanthium and style sometimes forming a secondary pollen presenter and pollendosing structure; ovary superior to inferior, (1)2-4-locular, with 1(2) ovules in each locule, ovules anatropous, basal and erect. Fruit indehiscent, winged or not, schizocarpic, capsular, rarely explosively dehiscent, or a more or less fleshy drupe with 1-4 indehiscent, rarely dehiscent pyrenes. Seeds with thin, oily albumen, sometimes exalbuminous, embryo large, oily, straight or rarely bent. An almost cosmopolitan family of 52 genera and about 925 species.
K. Kubitzki (ed.), Flowering Plants · Dicotyledons © Springer-Verlag Berlin Heidelberg 2004
VEGETATIVE MORPHOLOGY. Architecture is intermediate between Attim's and Raux's (Ziziphus), or between Koriba's and Raux's (Ziziphus, Paliurus) models (Tourn et al. 1992). Dichasial sympodia are common: the apical meristem of orthotropic shoots ceases growth or produces a spine, while buds of two distal nodes continue the growth. Leaves usually subtend a single bud, less commonly serial buds (Colletieae, Gouania, Ziziphus, Tourn et al. 1991). The lowermost serial bud can form vegetative long shoots, short -shoots, or flowering shoots, and the distal bud often produces a spine that may ramify (Tortosa et al. 1996). Spinyness is absent only in Gouanieae and Ventilagineae but pervasive only in the Colletieae. Twining shoots occur in Berchemia, Ziziphus, Ventilago and Smythea, and circinate tendrils in Gouania, Reissekia and Helinus. Rhizomes were reported